/* Calculate the inverse discrete cosine transform of a RenderedOp.

 @Copyright (c) 2003-2005 The Regents of the University of California.
 All rights reserved.

 Permission is hereby granted, without written agreement and without
 license or royalty fees, to use, copy, modify, and distribute this
 software and its documentation for any purpose, provided that the
 above copyright notice and the following two paragraphs appear in all
 copies of this software.

 IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
 FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
 THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
 SUCH DAMAGE.

 THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
 PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
 CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
 ENHANCEMENTS, OR MODIFICATIONS.

 PT_COPYRIGHT_VERSION 2
 COPYRIGHTENDKEY

 */
package ptolemy.actor.lib.jai;

import java.awt.image.renderable.ParameterBlock;

import javax.media.jai.JAI;
import javax.media.jai.RenderedOp;

import ptolemy.actor.lib.Transformer;
import ptolemy.data.type.BaseType;
import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;

//////////////////////////////////////////////////////////////////////////
//// JAIIDCT

/**
 Calculate the inverse discrete cosine transform of an image.  The output
 image data is of a high resolution (doubles), not suitable for
 displaying or saving.  To display or save the output of this image,
 use the {@link JAIDataConvert} actor to cast the data to an appropriate type
 (for instance, byte).  The output is zero-padded in each dimension to
 the next power of two (unless it already is a power of two in which case
 nothing happens).

 <p>No JAIDataConvert actors should be used in between a JAIDCT and JAIIDCT
 actor, unless if loss of spectral information is okay (or even desired).

 @see JAIDataConvert
 @see JAIDCT
 @author James Yeh
 @version $Id$
 @since Ptolemy II 3.1
 @Pt.ProposedRating Red (cxh)
 @Pt.AcceptedRating Red (cxh)
 */
public class JAIIDCT extends Transformer {
    /** Construct an actor with the given container and name.
     *  @param container The container.
     *  @param name The name of this actor.
     *  @exception IllegalActionException If the actor cannot be contained
     *   by the proposed container.
     *  @exception NameDuplicationException If the container already has an
     *   actor with this name.
     */
    public JAIIDCT(CompositeEntity container, String name)
            throws IllegalActionException, NameDuplicationException {
        super(container, name);
        input.setTypeEquals(BaseType.OBJECT);
        output.setTypeEquals(BaseType.OBJECT);
    }

    ///////////////////////////////////////////////////////////////////
    ////                         public methods                    ////

    /** Fire this actor.
     *  Output the inverse discrete cosine transform of the inputted
     *  image.
     *  @exception IllegalActionException If a contained method throws it.
     */
    public void fire() throws IllegalActionException {
        super.fire();

        ParameterBlock idctParameters = new ParameterBlock();
        JAIImageToken jaiImageToken = (JAIImageToken) input.get(0);
        RenderedOp oldImage = jaiImageToken.getValue();
        idctParameters.addSource(oldImage);

        RenderedOp newImage = JAI.create("idct", idctParameters);
        output.send(0, new JAIImageToken(newImage));
    }
}